The field of this invention relates to machine tool equipment and more particularly to a support apparatus for the worktable of the machine tool to support the worktable so that the operating planar surface of the worktable is located precisely within a given horizontal plane.
Machine tools are in exceedingly common usage. The typical construction of a machine tool utilizes a tool supporting column which is positioned is a spaced relationship above a worktable. This worktable is mounted on a knee. The worktable is movable along an X, Y and Z axis. Also, the machine tool itself is to be movable along the vertical axis (Z-axis) toward and away from the worktable.
A substantial amount of machining operations require accuracy to several thousandths of an inch. Even though the worktable is constructed of a solid, rigid piece of metal, this worktable will have a tendency to sag slightly at its ends since it is supported at a single point of connection located intermediate the ends. In essence, each end of the worktable is cantilevered with respect to the center of the worktable. When the workpiece, which frequently constitutes a rather heavy-weighted object, is placed on the table, further sagging occurs. Now when it is desired to create a machining operation within a certain tolerance of a few thousandths of an inch, this sagging of the worktable absolutely prevents such a tolerance being obtained.